CPTSV(l)		LAPACK routine (version	1.1)		     CPTSV(l)

NAME
  CPTSV	- compute the solution to a complex system of linear equations A*X =
  B, where A is	an N-by-N Hermitian positive definite tridiagonal matrix, and
  X and	B are N-by-NRHS	matrices

SYNOPSIS

  SUBROUTINE CPTSV( N, NRHS, D,	E, B, LDB, INFO	)

      INTEGER	    INFO, LDB, N, NRHS

      REAL	    D( * )

      COMPLEX	    B( LDB, * ), E( * )

PURPOSE
  CPTSV	computes the solution to a complex system of linear equations A*X =
  B, where A is	an N-by-N Hermitian positive definite tridiagonal matrix, and
  X and	B are N-by-NRHS	matrices.

  A is factored	as A = L*D*L**H	or A = U**H*D*U, and the factored form of A
  is then used to solve	the system of equations.

ARGUMENTS

  N	  (input) INTEGER
	  The order of the matrix A.  N	>= 0.

  NRHS	  (input) INTEGER
	  The number of	right hand sides, i.e.,	the number of columns of the
	  matrix B.  NRHS >= 0.

  D	  (input/output) REAL array, dimension (N)
	  On entry, the	n diagonal elements of the tridiagonal matrix A.  On
	  exit,	the n diagonal elements	of the diagonal	matrix D from the
	  factorization	A = U**H*D*U or	A = L*D*L**H.

  E	  (input/output) COMPLEX array,	dimension (N-1)
	  On entry, the	(n-1) subdiagonal elements of the tridiagonal matrix
	  A.  On exit, the (n-1) subdiagonal elements of the unit bidiagonal
	  factor L from	the L*D*L**H factorization of A.  E can	also be
	  regarded as the superdiagonal	of the unit bidiagonal factor U	from
	  the U**H*D*U factorization of	A.

  B	  (input/output) COMPLEX array,	dimension (LDB,N)
	  On entry, the	N-by-NRHS right	hand side matrix B.  On	exit, if INFO
	  = 0, the N-by-NRHS solution matrix X.

  LDB	  (input) INTEGER
	  The leading dimension	of the array B.	 LDB >=	max(1,N).

  INFO	  (output) INTEGER
	  = 0:	successful exit
	  < 0:	if INFO	= -i, the i-th argument	had an illegal value
	  > 0:	if INFO	= i, the leading minor of order	i is not positive
	  definite, and	the solution has not been computed.  The factoriza-
	  tion has not been completed unless i = N.


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